S&S Super Stock Alternator Style Crankcase for Harley Davidson 1970-84 Shovelhe Machined to accept the stock oil filter assembly introduced on some 1992 model Big Twins. This convenient, accessible location can be utilized to simplify installation of an oil filter in custom applications Machined to accept 81-91 or 92-99 style oil pumps and are machined for the stock 81-99 style oil distribution system The return oil pick-up passage to the return side of the oil pump has been relocated in order to avoid the turbulence caused by the oil pump drive gear. S&S Big Twin cases optimize crankcase oil scavenging efficiency by using a ported design breather passageway and a breather window that is machined to maximum timing specification. For Evolution style engines, the engine builder has the option of venting the crankcase breather from the crankcase, through the cylinder heads, or both.